Zoölogy: The Science of Animal Life Popular Science Library, Volume XII (of 16), P. F. Collier & Son Company, 1922

"Zoölogy: The Science of Animal Life" by Ernest Ingersoll is an early 20th-century exploration into the world of animals. This book journeys through the wide range of creatures on Earth, from the simple to the complex, showing how different species rely on each other in their environments. Readers will discover how animals are grouped and sorted, as well as getting an overview of early theories about where life comes from. The book begins by thinking about the age-old question of life's beginnings, looking at how people have tried to understand nature and how science has grown over time. It presents various ideas about how life might have started on our planet, like theories about meteorites and spontaneous creation. It stresses the importance of studying living things and their chemical makeup to truly grasp the secret of life, explaining cells and the role of chlorophyll in bringing plants and animals together. This beginning sets the stage for a journey into the diverse animal kingdom that is at the heart of the book.